1. Field of the Invention
The present invention relates generally to an apparatus for assembling electronic and/or electric parts, such as an IC chips to a base member, such as a substrate of a circuit board. More specifically, the invention relates to an electronic and/or electric parts assembling apparatus which is particularly adapted for assembling parts having connector pins or legs to be inserted into openings formed through a substrate.
2. Description of the Background Art
Japanese Patent First (unexamined) Publication (Tokkai) Showa No. 51-149562 and Japanese Patent Second (examined) Publication (Tokko) Showa No. 49-9824 discloses an electronic parts assembling apparatus for assembling electronic parts to a substrate. Such apparatus has a chucking mechanism chucking an electronic part to be assembled. The chucking mechanism is driven on a two-dimensional coordinate system formed on a plane substantially in parallel to a base member, such as a substrate of a circuit board, by means of a transverse driving mechanism. The chucking mechanism is also driven along an axis substantially perpendicular to the aforementioned two-dimensional coordinate system toward and away from the base member by means of an axial driving mechanism. The electronic parts as a workpiece is carried by the chucking mechanism to a position in the aforementioned coordinate system, to assemble the part onto the base member, by the transverse driving mechanism. Subsequently, the chucking mechanism is driven toward the base member to assemble the electronic part to the base member by inserting a pin or a leg thereof into an opening formed through the base member.
In such conventional apparatus, the chucking mechanism maintains the part until the pin is fully inserted. Faulty insertion of the pin is detected by detecting stress strain generated at a clinch edge of an anvil mechanism by means of strain gauge or piezoelectric element.
In the conventional apparatus set forth above, because the chuck mechanism is driven toward the base member by means of the axial driving mechanism carrying the electronic part, the pin tends to be bent or, in the worst case, damaged when the position of the pin is offset from the opening for insertion to insert. On the other, when the electronic part with more than one pin is provided, it is possible to detect faulty insertion after clamping one or more pins by means of the clinch edge. Namely, when one or some of the pins are accurately inserted and clamped, faulty insertion of one of the pins cannot be detected until the clinch edge reaches the pin inserted in failure. In such case, the parts assembled in failure have to be removed from the base before releasing the clamped pin from the base. This operation has to be done manually.